Upon Further Review

I was cleaning up the book from yesterday's post, "The Posthumous Papers of the Pickwick Club (Part One)" by Dickens and I noticed a folded brown paper sticking out of the side. I must have missed it yesterday:

Illustration; the paper measures 8.5 inches by 12 inches. I'm unsure of the materials used, it looks like the outline was sketched in pencil and colored in.